Log Lin, where

[Christopher Tay]

What’s your original source format ?

Are you using a 3DLUT ?

-chrispy

[Robin Erard]

Hello,

I’m using RED Material without 3Dlut. But the lab (35mm print) would like DPX in LOG.

All the best

Robin

réalisateur, scénariste, monteur
http://www.robinerard.ch

[Christopher Tay]

How would you know the accuracy if you grade without a 3DLUT for the film stock that you’re printing to ?

-chrispy

[Robin Erard]

Hello,

Good question. The lab will adapt the print-light according to the colorgrading. They apply a Rec709->LOG (3D Lut).

The last film of Godard has been made like that, the colorist gave the material to the lab and the lab had to find the solution to print as close as the video monitor.

But my question was not this one…

All the best

Robin

réalisateur, scénariste, monteur
http://www.robinerard.ch

[Peter Chamberlain]

HI, If you have log source material and no input or output LUT’s that’s what Resolve renders. If you have true linear, or TV gamma linear, that’s what gets rendered.
If you have linear material and need a log render, us a lin to log LUT in the output luts section of the config LUTs screen. This LUT will be applied to the timeline when rendering.

That being said, its common for film labs to be able to accept a Rec.709 calibrated TV Gamma image and for them to do the TV gamma to Log transform based on their film recorder, film stock and chemical baths.
Peter

[Robin Erard]

Hi, thank’s.

Then if I input a Prores422 HD, normally in Rec709 (I think), I grade between 64-940, Resolve will render in Rec709. But when I import these rendered DPX to Apple Color it interprets it like a 0-1023 signal (linear). Is it normal ?

Does it mean that Resolve always output 0-1023 signal but sometimes in Log, sometimes in Lin ?

Robin

réalisateur, scénariste, monteur
http://www.robinerard.ch

[Vladimir Kucherov]

If I remember correctly what you write on the DPX is one thing, and what the header is is another.

The header should only tell the program how to interpret the footage, or basically, what kind of input LUT to throw on. I think this is what Color does (and you can manually override this)

How you write the data is otherwise separate. So if you grade your footage to Rec 709 and then bake in a Lin to Log LUT, I *think* you should have proper log DPXs, with maybe incorrect or missing headers (because I haven’t seen anywhere in DaVinci where I can define a DPX header).